Electric-lighting system



(No Model.) 2 Sheets-Sheet 1.

J. 0. MAYRHOPER. ELECTRIC LIGHTING SYSTEM. No. 552,496. Patented Dec. 31, 1895.

wibnwoao km ethane/1 W ANDREW B GRAHAM PHOTO'UTMD WASHINGTON DC (No Model.) 2 Sheets-Sheet 2.

J. O. MAYRHOPER.

ELECTRIC LIGHTING SYSTEM.

- ANDREW asRAHAM PHOYO Lnno WASHINGTORDC UNITED STATES PATENT OFFICE.

JOSEPH CARL MAYRHOFER, OF NE\V YORK, N. Y., ASSIGNOR TO DENMAN THOMPSON, OF XVEST SIVANZEY, NEV HAMPSHIRE.

ELECTRIC-LIGHTING SYSTEM.

SPECIFICATION forming part of Letters Patent No. 552,496, dated December 31, 1895.

Application filed July '5, 1895. Serial No. 555,085. (No model.)

To aZl whom it may concern: of three switches w, r and bl. Three of these Be it known that I, J OsEPH CARL llIAYE- switches with circuit connections are shown HOFER, a citizen of the United States, residbecause it is usually desired to control lamps ing at New York city, in the county and State of three clorswhite, red and blue-but the 5 5 of New York, have invented a certain new number of switches will correspond wit-l1 the and useful Improvement in the Regulation of number of colors which the lamps of the par- Electric Lights for Theaters, of which the folticular plant have, and this number may be lowing is a specification. two or more. Each of these switches has a The object I have in view is to provide apcentral pivoted piece 0 of inverted-U shape, 60 1o paratus for the regulation and control of the the opposite sides of which are insulated from electric lights in a theater, whereby in a simeach other, and with the pivots of the U- ple and effective manner the different colors shaped piece 0 are connected the wires 14 and and intensities of light desired canbe secured. 15, 16 and 17, and 1S and 1.9,each pair connm In the accompanying drawings, forming stituting the two outside wires for the three part hereof, Figure 1 is a diagram illustrating wire circuit which includes the lamps of one one section of my apparatus and its conneccolor. The neutral or middle wires of these tions. Fig. 2 is a diagram showing the eircircuits are numbered 20, 21 and 22. These cuit connections for one series of lamps, such wires include suitable safety-catches 1), prefas one of the rows of borderlights of a theater erably arranged with one safety-catch norand Figs. 3 and a are illustrative diagrams mally in circuit and with an idle safety-catch showing the principle of operation. adapted to be thrown in by a swinging latch The regulator A, Fig. 1, is preferably of the when the first one breaks. The circuit-wires construction described in another application 14 to 22 are extended to the lamps 10"?" bl, of even date herewith. It is composed of two which constitute one group of the theater resistance-coils R R connected to two sets of lights-as, for instance, the lights of a single commutator-bars a 1), over which play comborder.

mutator-brushes carried by cross-bars c d, the The method of operating the apparatus will commutator-brushes at the opposite ends of be understood by reference to the diagrams the cross-bars being insulated from each other Figs. 3 and 4:, in which (for clearness of illus- 8o and making contact also with circuit-strips tration) two lighting-circuits are shown 6 f. Either one or both of the cross-bars are namely, the circuit 14; 15 2O controlling the adapted to be locked to a worm-shaft g, which white lamps, and the circuit 16 17 21 controlis operated bya shaft h through beveled gearling the red lamps-but it should be underwheels, which shaft is connected with other stood that the lamps of these two circuits are 8 5 c 5 similar regulators. The resistance-coils are grouped together, as shown in Fig. 2. If the connected at intervals with the plates of the switch w is thrown to the left and the switch two commutators. r is thrown to the right, as illustrated in Fig.

1 2 are the positive and negative conduc- 3, the white lamps will be connected with the tors of the supplying-circuit,and3 is the neucircuit 6 7 from the tops of the resistance- 90 4o tral conductor of the supplying-circuit, a coils and will receive the full pressure of the three-wire circuit being illustrated. The concurrent, while the red lamps will be connected ductors 1 2 are connected by wires 4 5 with with circuit 8 9 from the bottoms of the rethe contact-strips e f of the regulator. Oonsistance-coils and will have their current dinections 6 and 7 are taken from the upper minished by the resistance of the coils, since 5 5 ends of the coils R R independently of the both cross-bars 0 (Z are at the upper ends of commutators, and similar connections 8 9 are the coils. Now if both cross-bars 0 cl are taken from the lower ends of the coils. These moved together toward the other end of the connections 6, 7, S and 9 terminate in dis coils, resistance will be gradually introduced tributing-blocks 2' j Z. From these distribinto the circuit of the White lamps and will I00 0 uting-blocks connections 10, 11, 12 and 13 exbe gradually cut out of the circuit of the red tend to the stationary contacts m m and a n lamps, and the white lamps will be diminished neously, while if the two cross-bars are moved simultaneously away from the center of the coils both sets of lamps will be increased in candle-power simultaneously. By this means the shading of one color into another can be accomplished, or two colors can be used at the same time with any desired relative degree of brightness. If the lighting-circuits are two-wire circuits, as illustrated in Fig. 4:, the same effects can be attained by using onehalf of the regulator, and it is also evident, as shown in Fig. 1, that more than two lampcircuits can be connected with the same regulator; but if three lamp-circuits are put in connection with the regulator at once two of the circuits will be under the control of one of the cross-bars and will be regulated as one circuit. As illustrated in Fig. 2, the lamps of diiferent color will be arranged in succession in a group of lamps, and if a three-wire circuit is employed the lamps of each color are preferably divided between the two sides of the circuit, so as to avoid fluctuation in the current during regulation, due to changing the balance between the two sides of the three-wire system.

lVhat I claim is 1. In a theater light regulator, the combination with a resistance coil, a series of commutator plates connected at intervals with said coil, and a contact movable over said commutator plates and connected with the supply circuit, of two or more lighting circuits, and an independent switch for one side of each lighting circuit having connections with both ends of the resistance coil whereby said lighting circuits may at the same time be connected with the same end or with different ends of said resistance coil, the other sides of said lighting circuits being connected with the supply circuit, substantially as set forth.

2. In a theater light regulator, the combination with a resistance coil, a series of commutator plates connected at intervals with said coil, and two contacts connected with the supply circuit and movable over said commutator plates, of two or more lamp circuits and two or more independent switches for connecting one side of each of said lamp circuits independently with either end of said resistance coil, the other sides of said lamp circuits being connected with the supply circuit, substantially as set forth.

3. In a theater light regulator, the combination with two resistance coils, two series of commutator plates connected with said resistance coils, and a pair of contacts connected together and moving simultaneously over said commutator plates, said contacts being connected with the outside wires of a three-wire supply circuit, of two or more three-wire lamp circuits, and switches for connecting the outside wires of each of said lamp circuits independently with the ends of said resistance coils, the central wires of said lamp circuits being connected with the middle wire of the supply circuit, substantially as set forth.

4;. In a theater light regulator, the combination with two resistance coils, two sets of commutatorplates connected with said coils, and two pairs of contacts independently and simultaneously movable over said contact plates, said movable contacts being connected with the outside wires of a three-wire supply circuit, of two or more three-wire lamp circuits, and switches connecting the outside wires of each of said lamp circuits independently with the ends of said resistance coils, the middle wires of said lamp circuits being connected with the middle wire of the supply circuit, substantially as set forth.

This specification signed and witnessed this 20th day of June, 1895.

J OS. CARL MAY 'HIOFER.

\Vitnesses:

EUGENE CONRAN, JoHN R. TAYLOR. 

